US President Donald Trump’s nominee to lead federal health department says he is ‘not anti-vaccine’ as Democrats zero in on his past remarks.

Robert F Kennedy Jr has faced a barrage of questions about his history of spreading anti-vaccine conspiracy theories during a contentious United States Senate hearing on his nomination to be President Donald Trump’s health secretary.

Kennedy, who has been picked to lead the US Department of Health and Human Services (HHS), spent most of Wednesday’s hearing seeking to dispel the idea that he is “anti-vaccine”.

“News reports have claimed that I am anti-vaccine and anti-industry — I am neither. I am pro-safety,” he told the Senate Finance Committee.

“I believe that vaccines play a critical role in healthcare,” he added.

But Kennedy, a former environmental lawyer and son of the late US Senator Robert F Kennedy, has become a politically polarising figure and one of Trump’s most controversial cabinet nominees.

Critics denounced him for a slew of past false statements questioning the safety of vaccines, including during the COVID-19 pandemic.

At the start of Wednesday’s hearing, the top Democrat on the panel, Senator Ron Wyden, said Kennedy has “embraced conspiracy theories, quacks [and] charlatans, especially when it comes to safety and efficacy of vaccines”.

“He has made it his life’s work to sow doubt and discourage parents from getting their kids life-saving vaccines. It has been lucrative for him and put him on the verge of immense power,” Wyden said.

I just pressed RFK Jr. on his stance on vaccines. It’s a simple question, and the guy Trump wants running our nation’s health care system can’t give a straight answer. https://t.co/F98ThuX3q0

— Ron Wyden (@RonWyden) January 29, 2025

Other Democrats also pointed at some of Kennedy’s past statements to question his ability to lead HHS, which oversees healthcare programmes in the country.

Senator Michael Bennet asked the nominee about his prior assertion that the COVID-19 pandemic was engineered to target white and Black people, while sparing Ashkenazi Jews and Chinese people.

Kennedy responded that he was citing federal research, without elaborating.

Bennet also asked Kennedy about a claim that Lyme disease is “likely a militarily engineered bioweapon”.

“I probably did say that,” Kennedy responded.

But Republicans, who control the 100-seat Senate, have largely supported Kennedy’s nomination.

All of Trump’s cabinet picks have been confirmed so far, with Vice President JD Vance casting a tie-breaking vote last week to push through Pete Hegseth’s confirmation as the new head of the Pentagon.

Kennedy, who will face another hearing before a separate Senate committee on Thursday, needs 50 votes to be confirmed.

Reporting from Washington, DC, on Wednesday afternoon, Al Jazeera correspondent Mike Hanna noted that the hearing went largely as expected, with “softball questions” from Republicans and more pointed queries from Democrats.

“Republicans appear to be totally in support [of Kennedy’s nomination], although there were some questions about his ability to manage a massive, sprawling insurance system in this country,” Hanna said.

Kennedy was also pressed on his stance on abortion, Hanna added. While his position has shifted over the years, Kennedy said on Wednesday that he would uphold the Trump administration’s abortion policies, including on the availability of the pill mifepristone.

Kennedy ran as an independent in the 2024 presidential race before dropping out and endorsing Trump in August.

He said on Wednesday that, if confirmed, he plans to deliver on a promise to “Make America Healthy Again” — a play on Trump’s “Make America Great Again” slogan.